Leakage seal for shafts



Aug. 31 1926.

A. R. EARNSHAW LEAKAGE SEAL FOR SHAFI'S Filed August 6, 1925 Fla I.

INVENTOR:

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2 ated therewith.

Patented Aug. 31, 1926.

UNITED STATES ARTHUR a. naansnaw; or WYNNEWOOD,

MANUFACTURING CORPORATION, OF PORATION OF DELAWARE.

PENNSYLVKNIA, ASSIGNOR TO EARNBHAW PHILADELPHIA, PENNSYLVANIA, A. COR- LEAKAGE SEAL FOR SHAFTS.

Application filed August 6, 1923. Serial No. 655,904.

My invention relates to means useful in rendering journals for shafts of compressors, pumps and thelike proof against fluid leakage and is sion of a metallic packing for the purpose indicated, characterized by the absenceof stuffing such as ordinaril curing fluid-tightness and capable of maintaininga perfect and reliable seal notwithstanding lateral displacement of the shaft as is likely to occur under vibratory flexure at high speeds of rotation.

How this desiderata ma be attained will become readil apparent rom the detailed description w ich follows of a typical embodiment of my invention.

In the drawings, Fi I, is a fragmentary detail sectional view of a shaft journal conveniently showing my invention incorpor- I 'Figs. II and III are perspective illustrations of the two elements comprised in my invention, which cooperate to maintain a A fluid tight seal at the shaft journal. As herein shown, the shaft lcthat is to be packed is journalled in a replaceable bushing bearing 2 appropriately-secured in the casing wall of a compressor or pump whereof a portion is indicated at 3. From the exterior of this wall '3 projects a boss 4 having an axial cavity with a shoulder 5 that affords a seat for a packing gasket 6 against which rests a comparatively thin metallic dia hragm or vibratory disk 7. The circum erential margin of this diaphragm 7 is forced into fluid-tight engagement with the packing gasket 6 by a gland 8 screwed into the boss 4. The diaphragm 7 has an extended outwardly-projecting axial sleeve 9 that surrounds the shaft 1, but with interposition of an annular interspace as indicated conventionally by the shading at 10 in Fig.'I, so as to' be capable of independent lateral yielding movement under the flexibility of the diaphragm 7. The free end of the sleeve9, (see Fig. II), has a rounded cross-sectional configuration as at 11 to fit snugly within a correspondingly configured annular groove 12 (Figs. I, and III), in the contiguous end face of. a collar 13 that is detachably secured to the shaft. 1. Any ap ropriate means may be employed to secure the collar directed toward proviemployed in se-.

to compensate positional of the flexibility of the is important to note in this connection that 13 such for example as herein shown in the form of a nut 14 designed to engage with a. reduced integral tapered threaded axial prolongation 15 of said collar 13. In ractice I have found that if the wall 0 the tapered prolongation 15 is made relatively thin, a reliable bindin effect may be had through co-operation of the nut 14 without necessitating splitting of said prolongation. In order to ermit the use of a suitable tool to hold t e collar 13 against rotation as the nut 14 is applied, I flatten the body portion of the collar at diametrically opgosite'sides as shown at 16 in Fig. III. The

iaphragm 7 is subject to pressure influence' from the interior of the casing 3 through provision of one or more communication ducts 17 that lead to an internal annular recess 18 in the hollow of the boss 4. If desired such pressure influence may be augmented by means of a helical spring 19 in COIIIPI'BSSIOD} in the interval between the bushing 2 and the-"inner end of the sleeve 9.

In operation, the inner face of the diaphragm 7 under assistance of the sprin 19 serves to maintain the free end 11 of the sleeve 9 firmly seated in the groove 12 of the rotating collar 13 and thereby establishes a perfect,

fluid-tight joint at this region. Such engagement by reason of the interlock between the pressure exerted upon the .outer end of the sleeve 9 and the contiguous face of the collar 13 will obviously be-malntained notwithstanding any lateral displacement of said collar under vibratory flexure of the shaft 1 at high speeds, the

sleeve 9 adaptingitself readily at all times changes by virtue diaphgram 7. It

while remaining at all times hermetically sealed. This feature inheres from the able nature of the diaphra 7, that allows the sleeve 9 to move an compensate for pliany wear arising between its free end 11 and thecomplementary surface of the groove 12.

r The inherent simplicity of my invention, it will be seen, offsets the possibility of derangement or necessity for frequent adjustment in use, and it will also be apparent that itslongevity will greatly excel shaftpackings wherein stuflings are relied upon to secure fluid-tightness.

Having thus described my invention, I claim: v r

1. In a leakage seal for shafts comprising a pressure influenced diaphragm havingan axial sleeve adapted to -fit loosely about the shaft to be sealed, the combination of ,a collar having a screw-threaded taper prolongation and co-operative nut by which it is fixed to the shaft, said collar 2 having an annularly grooved end with which the complementarily configured contiguous end of the sleeve co-operate's hermetically, while accommodating vibratory flexure of the shaft.

2. In a leakage seal for shafts com rising a pressure influenced diaphragm aving an extended axial sleeve ada ted to fit freely about the shaft to be seale the combination of a collar having a screw-threaded taper prolongation and co-operative nut by which it is fixed on the shaft, said collar having an annularly grooved end in cooperative abutment with the contiguous end of the sleeve to afl'ord a hermetical seal and.

accommodate vibratory flexure of the shaft. In testimony whereof, I have hereunto signed my name at Philadelphia, Pennsylvania, this'3rd day of August, 1923.

ARTHUR R. EARNSHAW. 

